Driving system for terry motion members in cloth-shifting-type pile loom

ABSTRACT

A cloth-shifting-type pile loom includes a first driving mechanism for driving a first terry motion member disposed at a feeding side of the pile loom, and a second driving mechanism for driving a second terry motion member disposed at a take-up side of the pile loom. Each of the driving mechanisms includes a rocking lever that is driven in a rocking motion in a displacement direction of the corresponding terry motion member by a corresponding one of driving means. The rocking lever of the first driving mechanism and the rocking lever of the second driving mechanism have a connection member disposed therebetween such that the connection member connects the two rocking levers.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a driving system for terry motionmembers, and specifically, to a driving system for terry motion membersin a cloth-shifting-type pile loom including a first driving mechanismfor driving a first terry motion member disposed at a feeding side ofthe pile loom; and a second driving mechanism for driving a second terrymotion member disposed at a take-up side of the pile loom, each drivingmechanism including a rocking lever that is driven in a rocking motionin a displacement direction of the corresponding terry motion member bya corresponding one of driving means.

2. Description of the Related Art

Japanese Unexamined Patent Application Publication No. 2-47334 andJapanese Unexamined Patent Application Publication No. 11-172552disclose examples of a cloth-shifting-type pile loom mentioned above.

A pile loom disclosed in Japanese Unexamined Patent ApplicationPublication No. 2-47334 is provided with a back roller defining afeeding-side terry motion member for guiding ground warp yarns, and abreast beam defining a take-up-side terry motion member for guidingwoven cloth. The back roller and the breast beam are supported bycorresponding rocking levers. Each of the rocking levers is driven in arocking motion by one of dedicated driving motors defining drivingmeans.

On the other hand, according to Japanese Unexamined Patent ApplicationPublication No. 11-172552, a ground-weaving tension roller, whichdefines a feeding-side terry motion member, and a take-up-side terrymotion member are individually driven by corresponding cam mechanismsdefining driving means and by corresponding driving mechanisms includingrocking levers that are driven in a rocking motion by the correspondingcam mechanisms.

According to these types of pile looms, the displacement amounts and thedisplacement timings, for example, can be set individually for thefeeding-side terry motion member and the take-up-side terry motionmember. Consequently, the displacement amount, for example, for only thefeeding-side terry motion member may be set such that the displacementamount is determined not only in view of the terry motion but also inview of compensating for a tension fluctuation caused by, for example,shedding motion of warp yarns. This is significantly advantageous incomparison with a structure in which the feeding-side terry motionmember and the take-up-side terry motion member are drivensimultaneously via a driving mechanism linked with common driving means.Such a comparative structure is described as conventional art inJapanese Unexamined Patent Application Publication No. 11-172552.

However, for driving the feeding-side terry motion member and thetake-up-side terry motion member individually with corresponding drivingmeans, as in the pile looms mentioned above, the tension of the warpyarns and the tension of the woven cloth directly act upon thecorresponding driving means. As a result, this increases the amount ofload acting on each driving means.

In detail, the warp tension applied to the feeding-side terry motionmember and the cloth tension applied to the take-up-side terry motionmember act as forces that bias the two terry motion members toward eachother. If the two terry motion members are driven via a single rockinglever that is rocked by common driving means, as in the conventional artdescribed in Japanese Unexamined Patent Application Publication No.11-172552, the effect of the warp tension and the cloth tension is notsignificant since the forces generated in opposite directions inresponse to the warp tension and the cloth tension simultaneously act onthe single rocking lever and thus counterbalance each other. Incontrast, when the two terry motion members are individually driven bycorresponding driving means, each of the driving means receives aunidirectional load via the corresponding rocking lever. In this case,since such a load constantly acts on each of the driving means inresponse to the corresponding tension, if each driving means is, forexample, a driving motor, as used in Japanese Unexamined PatentApplication Publication No. 2-47334, such a load may induce an increasein power consumption or damaged driving means at an early stage of use.On the other hand, if each driving means is a cam mechanism, as used inJapanese Unexamined Patent Application Publication No. 11-172552, alarge amount of load may act on components such as a rotational shaft ofeach cam and a rocking shaft of each rocking lever, thus leading to wearabrasions and damages in these components at an early stage of use.

In Japanese Unexamined Patent Application Publication No. 2-47334, eachrocking lever driven in a rocking motion by the corresponding drivingmotor and a stationary section of the pile loom have a bias springattached therebetween, such that the bias spring absorbs the tension ofthe warp yarns. However, according to such a structure of JapaneseUnexamined Patent Application Publication No. 2-47334, even though theeffect of the warp tension or the cloth tension can be reduced, anadditional force that overpowers the spring force of each bias springmust be generated when the corresponding driving means drives thecorresponding terry motion member via the corresponding rocking lever inorder to form a pile fabric. Consequently, this increases the amount ofload acting on each driving motor during terry motion.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to reduce anamount of load, which is generated due to warp tension or cloth tension,acting on each of driving means provided for driving a corresponding oneof feeding-side and take-up-side terry motion members in order toprevent the driving means, for example, from being damaged at an earlystage of use.

According to an aspect of the present invention, a driving system forfirst and second terry motion members in a cloth-shifting-type pile loomis provided. The first terry motion member is disposed at a feeding sideof the pile loom and the second terry motion member is disposed at atake-up side of the pile loom. The driving system includes a firstdriving mechanism for driving the first terry motion member, the firstdriving mechanism including a first rocking lever that is driven in arocking motion in a displacement direction of the first terry motionmember by first driving means; a second driving mechanism for drivingthe second terry motion member, the second driving mechanism including asecond rocking lever that is driven in a rocking motion in adisplacement direction of the second terry motion member by seconddriving means; and a connection member disposed between the first andsecond rocking levers such that the connection member connects the firstand second rocking levers.

Furthermore, the connection member may be an elastically deformablemember that is elastically deformed when receiving forces that bias thefirst and second rocking levers toward and away from each other.Moreover, the connection member may be a compression spring attachedbetween the first and second rocking levers.

In the driving system for the terry motion members in thecloth-shifting-type pile loom according to the present invention, sincethe two rocking levers are linked with each other via the connectionmember, the forces applied to the rocking levers in response to the warptension and the cloth tension counterbalance each other. Thus, the loadacting on the driving means corresponds only to inertia forces andfrictional forces of, for example, the levers and the rollers, and istherefore significantly small. Moreover, even when different drivingamounts are set for the two terry motion members such that the warptension and the cloth tension become different temporarily, the loadacting on each driving means corresponds only to the difference inmagnitude of the these tensions. Consequently, such a load issignificantly small in comparison with a case where the load generatedin response to the warp tension or the cloth tension is applied directlyto each driving means. Furthermore, since the rocking levers of thecorresponding driving mechanisms are linked with each other via, forexample, a spring member as the connection member, none of the springforce of the spring member acts as driving resistance during the terrymotion. Even if such a spring force were to act as driving resistance,the magnitude of the driving resistance is significantly small. As aresult, the amount of load acting on each driving means during the terrymotion is accordingly small.

Moreover, since the connection member may be an elastically deformablemember that can be elastically deformed when receiving forces that biasthe two rocking levers toward and away from each other, the advantage inindividually driving the two terry motion members with the correspondingdriving means can be maintained. Furthermore, since the connectionmember may be a compression spring attached between the two rockinglevers, such an advantage can be achieved more readily.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a lateral view of a cloth-shifting-type pile-loom according toa first embodiment of the present invention;

FIG. 2 is a lateral view illustrating relevant components included inthe first embodiment of the present invention; and

FIG. 3 is a lateral view illustrating relevant components included in asecond embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention will now be described withreference to the drawings.

FIGS. 1 and 2 illustrate a first embodiment of the present invention. Apile loom 1 shown in FIG. 1 according to the present invention is acloth-shifting type which shifts the cloth fell during a pile-weavingoperation in order to form a pile fabric.

The cloth-shifting-type pile-loom 1 includes an upper warp beam 2 aroundwhich a plurality of pile warp yarns 4 are wound in a sheet-like manner,and a lower warp beam 3 around which a plurality of ground warp yarns 5are wound in a sheet-like manner. The pile warp yarns 4 are fed from thewarp beam 2, and are wound around two guide rollers 6, 6 and a pile-warptension roller 7 disposed at a downstream side of the guide rollers 6, 6so as to be supplied to woven cloth 8 and a cloth fell 9 via a heald(not shown) and a reed 10.

On the other hand, the ground warp yarns 5 are fed from the warp beam 3,and are wound around a ground-warp tension roller 15, which defines afeeding-side terry motion member. Similar to the pile warp yarns 4, theground warp yarns 5 guided by the tension roller 15 are then supplied tothe woven cloth 8 and the cloth fell 9 via the heald and the reed 10.

Together with each inserted weft yarn (not shown), the pile warp yarns 4and the ground warp yarns 5 form the woven cloth 8. The woven cloth 8 issubsequently guided by a cloth guide roller 16, which defines atake-up-side terry motion member, towards a take-up roller 11, a guideroller 12, and a guide roller 13 so as to be finally taken up by a clothroller 14.

In FIGS. 1 and 2, a pair of driving motors M1, M2 defining driving meansis provided such that the two driving motors M1, M2 respectivelycorrespond to the two rollers 15 and 16 defining the terry motionmembers. The two driving motors M1, M2 are fixed to one of side frames(not shown) of the pile loom 1 via, for example, brackets (not shown)such that output shafts m1, m2 of the respective driving motors M1, M2are disposed perpendicular to the traveling direction of the warp yarns.The driving motor M1 is linked with the ground-warp tension roller 15defining the feeding-side terry motion member via a first drivingmechanism 20, whereas the driving motor M2 is linked with the clothguide roller 16 defining the take-up-side terry motion member via asecond driving mechanism 30.

The first and second driving mechanisms 20, 30 will now be described indetail with reference to FIG. 2.

The first driving mechanism 20 includes a rocking lever 22 that can bedriven in a rocking motion by the driving motor M1; a supporting leverunit 24 for supporting the tension roller 15; and a linking rod 26 forlinking the rocking lever 22 and the supporting lever unit 24. Therocking lever 22 is supported in a rocking manner by a stationarysection of the pile loom 1, such as the side frame, via a spindle 22 a.Moreover, the rocking lever 22 is linked with the output shaft m1 of thedriving motor M1 via a crank lever 42 attached to the output shaft m1and via a link component 28.

The supporting lever unit 24 includes a pair of levers for respectivelysupporting two opposite ends of the ground-warp tension roller 15. Eachlever of the supporting lever unit 24 is supported in a rocking mannerby a stationary section of the pile loom 1, such as the correspondingside frame, via a spindle 24 a. Specifically, one of the levers of thesupporting lever unit 24 is shown in the drawing (i.e. a lever disposedat a side provided with the driving motor M1). The lever supports thetension roller 15 at an intermediate section of the lever, and moreover,is connected with a first end of the linking rod 26 at an end portion ofthe lever opposite to the end portion supported by the spindle 24 a.Furthermore, since a second end of the linking rod 26 is connected withthe rocking lever 22, the tension roller 15 and the driving motor M1 arelinked with each other via the first driving mechanism 20 defined by therocking lever 22, the linking rod 26, and the supporting lever unit 24.

Similarly, the second driving mechanism 30 includes a rocking lever 32which is supported in a rocking manner by a spindle 32 a and is linkedwith the output shaft m2 of the driving motor M2 via a crank lever 44and a link component 38; a supporting lever unit 34 which is supportedin a rocking manner by a spindle 34 a and which supports the cloth guideroller 16; and a linking rod 36 connected to the rocking lever 32 and toan end portion of one of levers of the supporting lever unit 34, the endportion of the lever being opposite to the end portion supported by thespindle 34 a. The second driving mechanism 30 link the cloth guideroller 16 to the driving motor M2.

The crank levers 42 and 44 are attached in a manner such that endportions of the crank levers 42 and 44 respectively connected with thelink components 28 and 38 are directed toward the feeding side of thepile loom 1 with respect to the corresponding output shafts m1 and m2 ofthe driving motors M1 and M2. This means that when the output shafts m1and m2 of the respective driving motors M1 and M2 are rotated by apredetermined angle, the corresponding rocking levers 22 and 32 aredriven in a rocking motion respectively around the spindles 22 a and 32a in the same direction by an amount corresponding to the rotationalangle of the output shafts m1 and m2. Furthermore, in response to thisrocking motion, the supporting lever units 24 and 34 are also rocked bythe same amount in the same direction as the rocking direction of therespective rocking levers 22 and 32. Thus, the tension roller 15 and thecloth guide roller 16 are rocked in the same rocking direction aroundthe respective spindles 24 a and 34 a, whereby the cloth fell 9 of thewoven cloth 8 is shifted.

In a driving system including the first and second driving mechanisms20, 30 for the terry motion members 15, 16 shown in the drawing, therocking levers 22 and 32 have a compression spring 46 attachedtherebetween, which defines a connection member. Specifically, twoopposite ends of the compression spring 46 are respectively attached toend portions of the rocking levers 22 and 32 that are opposite to theend portions supported by the spindles 22 a and 32 a.

According to this structure, the tension of the ground warp yarns 5 actsas a force that rocks the rocking lever 22 in the clockwise direction inthe drawing via the tension roller 15. On the other hand, the tension ofthe woven cloth 8 acts as a force that rocks the rocking lever 32 in thecounterclockwise direction in the drawing via the cloth guide roller 16.In other words, these forces bias the rocking levers 22 and 32 towardseach other, but since the two rocking levers 22 and 32 are linked witheach other via the compression spring 46, the forces acting on therocking levers 22 and 32 are applied back to themselves via thecompression spring 46 such that a balanced state is maintained.Accordingly, a load acting on each of the driving motors M1, M2 inresponse to the corresponding tension is extremely small.

Specifically, when the rocking levers 22 and 32 are in a resting stateor are rocked by the same amount at the same timing, the forces actingon these rocking levers 22 and 32 due to the warp tension and the clothtension are substantially the same since these tensions are balanced.Consequently, these oppositely-directed forces counterbalance eachother. Accordingly, the load acting on each of the driving motors M1, M2due to the warp tension or the cloth tension is extremely small (nearlyzero).

On the other hand, when the rocking levers 22 and 32 are rocked bydifferent amounts and/or at different timings, the magnitudes of thewarp tension and the cloth tension temporarily become different. Even insuch a case, the load acting on each of the driving motors M1, M2corresponds only to the difference in magnitude of these tensions. Forthis reason, in comparison with a typical device in which the loadgenerated in response to each tension is applied directly to thecorresponding motor, the load acting on each of the driving motors M1,M2 in the present invention is extremely small.

Furthermore, the compression spring 46 provided between the rockinglevers 22 and 32 for connecting the two levers and for receiving thecorresponding tensions applies hardly any driving resistance or only asignificantly small amount of driving resistance to the rocking levers22 and 32 during terry motion. Accordingly, this means that a loadacting on each of the driving motors M1, M2 due to the compressionspring 46 during the terry motion is extremely small.

Moreover, since the compression spring 46 is provided as the connectionmember for connecting the rocking levers 22 and 32, the distance betweenthe rocking levers 22 and 32 is adjustable. This means that the rockinglevers 22 and 32 can be adjustably rocked by different amounts and atdifferent timings. Consequently, even if such a connection member isapplied, an advantage in individually driving the feeding-side terrymotion member and the take-up-side terry motion member withcorresponding dedicated driving means can still be maintained.

According to the first embodiment, the rocking levers 22 and 32 and thecorresponding driving motors M1, M2 are respectively linked with eachother via the crank levers 42, 44 and the link components 28, 38. On theother hand, the present invention is not limited to this link structurebetween the rocking levers 22 and 32 and the respective driving motorsM1, M2. For example, as an alternative to the example shown in FIG. 2,the spindles 22 a and 32 a of the respective rocking levers 22 and 32may be driven directly by the corresponding driving motors M1, M2.

Furthermore, although the first embodiment describes an example in whichthe driving motors M1, M2 are provided as driving means for thecorresponding terry motion members, the present invention is not limitedto such a structure. For example, as in the previously-mentionedconventional art, the rocking levers 22, 32 of the respective drivingmechanisms 20, 30 may alternatively be driven in a rocking motion by cammechanisms provided for the corresponding rocking levers 22, 32. Such astructure will be described below in detail as a second embodiment ofthe present invention with reference to FIG. 3. In FIG. 3, componentsequivalent to those in the first embodiment are given the same referencenumerals, and descriptions of those components will thus be omitted.

FIG. 3 illustrates the second embodiment of the present invention. Inthe second embodiment, a pair of cam mechanisms 50, 60 is respectivelyprovided for the rocking levers 22, 32, and defines driving means fordriving the corresponding rocking levers 22, 32 in a rocking motion. Thecam mechanisms 50, 60 respectively include cams 52, 62 driven by a mainshaft 18 of the loom; and cam levers 54, 64 whose front end portionssupport cam followers 56, 66.

The cam levers 54, 64 are respectively fixed to the spindles 22 a, 32 athat securely support the rocking levers 22, 32. When the cam levers 54,64 are respectively rocked by the cams 52 and 62, the spindles 22 a and32 a are rotated so that the rocking levers 22, 32 are driven in arocking motion. Furthermore, the cam mechanisms 50, 60 are passive cammechanisms in which the cam levers 54, 64 are respectively biased towardthe cams 52, 62 with springs 58, 68 so that the cam followers 56, 66disposed at the front end portions of the cam levers 54, 64 areconstantly in contact with the cams 52, 62.

In this type of driving system including the driving mechanisms 20, 30for the terry motion members 15, 16, the tension of the ground warpyarns acts as a force that biases the rocking lever 22 in the clockwisedirection in the drawing via the ground-warp tension roller 15, and thesupporting lever unit 24 and the linking rod 26 of the first drivingmechanism 20. Furthermore, this force acts on the cam lever 54 via thespindle 22 a such that the cam follower 56 tries to move away from thecam 52. For this reason, the strength of the biasing force of the spring58 must be determined in view of the warp tension such that the camfollower 56 is prevented from moving away from the cam 52. However, ifthe biasing force of the spring 58 is large, a large amount of load maybe applied to a camshaft 52 a of the cam 52 and to contact surfaces ofthe cam follower 56 and the cam 52 when the cam lever 54 is to be rockedby the cam 52. This may possibly cause the cam 52 and the camshaft 52 ato become damaged.

On the other hand, the tension of the woven cloth acts as a force thatbiases the rocking lever 32 in the counterclockwise direction in thedrawing via the cloth guide roller 16, and the supporting lever unit 34and the linking rod 36 of the second driving mechanism 30. Furthermore,this force acts on the cam lever 64 such that the cam follower 66presses against the cam 62. For this reason, similar to the casedescribed above in which the spring 58 is given a large biasing force, alarge amount of load may be applied to a camshaft 62 a of the cam 62 andto contact surfaces of the cam follower 66 and cam 62 when the cam lever64 is to be rocked. Similarly, this may possibly cause the cam 62 andthe camshaft 62 a to become damaged.

In order to prevent such damages, the second embodiment of the presentinvention is provided with a connection member for connecting therocking levers 22 and 32. In FIG. 3, the connection member is defined bythe compression spring 46 as in the first embodiment. Accordingly, thewarp tension or the cloth tension is prevented from acting directly oneach driving means provided for the corresponding terry motion member.As a result, even if the tensions act on the corresponding rockinglevers 22, 32 so as to generate forces that bias the rocking levers 22,32 towards each other, these forces acting on the rocking levers 22, 32are applied back to themselves via the compression spring 46, whereby abalanced state can be maintained. Accordingly, this reduces the loadacting on each driving means, and therefore, prevents the problemsmentioned above.

Although the compression spring 46 is provided as the connection memberin the above embodiments, the connection member according to the presentinvention is not limited to a compression spring. For example, as analternative to the compression spring, the connection member may be, forexample, a leaf spring. If a leaf spring is to be used as the connectionmember, the leaf spring is preferably given a size such that the leafspring bends when the rocking levers 22 and 32 are most distant fromeach other.

Although the connection member is preferably a spring member thatreceives the forces that bias the two rocking levers 22 and 32 towardeach other and that also allows the rocking levers 22 and 32 to moveaway from each other as described above, the connection member mayalternatively be a rigid member if only the load acting on the drivingmeans is taken into consideration. In a case where such a rigid memberis used as the connection member, both driving means must be driven inexact synchronization with each other. Moreover, if the two rockinglevers 22 and 32 are linked with each other via the rigid member,although the two terry motion members cannot be driven by differentdriving amounts and at different timings, the load acting on each of thetwo driving means during the terry motion is less than in a case whereonly a single driving means is used. For this reason, small-size motorscan be used as the driving means. Accordingly, this is stilladvantageous in view of power consumption and costs.

Furthermore, the connection member may be attached to the rocking levers22 and 32 in a detachable and a replaceable manner. In this case, theconnection member may be removed or may be replaced with anotherconnection member depending on the weaving conditions. Specifically, theconnection member may be removed if a weaving operation is to beperformed in a state where the warp tension and the cloth tension areset low such that the load acting on the driving means in response tothe tensions is small. In this case, when the connection member becomesnecessary again, the same connection member may be reattached.Alternatively, if the subsequent weaving operation is directed toweaving another type of fabric after performing a weaving operationusing a spring member as the connection member, the connection membermay be changed from the spring member to the rigid member if the drivingamounts and the driving timings of the terry motion members do not needto be changed for the subsequent weaving operation. Furthermore, thewarp tension and/or the cloth tension could possibly change when, forexample, fabric to be woven is switched to another type or whenadjustments are made in other mechanisms. In such cases, the springmember may be replaced with another type that has, for example, adifferent spring constant and/or different length.

Furthermore, although the two driving means are disposed close to eachother in a central section of the loom with respect to the travelingdirection of the warp yarns, the positioning of the driving means is notlimited. In the present invention, the structure of the drivingmechanisms and the positioning of the driving means, for example, may bechanged in any desired manner as long as the connection member can beattached between the pair of rocking levers that are driven in a rockingmotion by the corresponding driving means in the displacement directionof the terry motion members.

The technical scope of the present invention is not limited to the aboveembodiments, and modifications are permissible within the scope andspirit of the present invention.

1. A driving system for first and second terry motion members in acloth-shifting-type pile loom, the first terry motion member beingdisposed at a feeding side of the pile loom and the second terry motionmember being disposed at a take-up side of the pile loom, the drivingsystem comprising: a first driving mechanism for driving the first terrymotion member, the first driving mechanism including a first rockinglever that is driven in a rocking motion in a displacement direction ofthe first terry motion member by first driving means; a second drivingmechanism for driving the second terry motion member, the second drivingmechanism including a second rocking lever that is driven in a rockingmotion in a displacement direction of the second terry motion member bysecond driving means; and a connection member disposed between the firstand second rocking levers such that the connection member connects thefirst and second rocking levers.
 2. The driving system according toclaim 1, wherein the connection member comprises an elasticallydeformable member that is elastically deformed when receiving forcesthat bias the first and second rocking levers toward and away from eachother.
 3. The driving system according to one of claims 1 and 2, whereinthe connection member comprises a compression spring attached betweenthe first and second rocking levers.